JP2000160261A - Method for supplying sintering raw material and supplying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the sufficient degree of sintering as the whole body and to improve the yield of the product sintered ore by acting magnetic force to the flowing of the sintering raw material with a magnetizing device set to the interval between a drum feeder and a pallet, attracting the magnetized sintering raw material to the lower layer side, supplying the carboneceous material in the upper part after much segregating the magnetized sintering raw material in the upper layer part of the raw material layer on the pallet and laminating. SOLUTION: A sintering raw material 2 is discharged by using a drum feeder 3 from an ore supplying hopper 1, and supplied onto the pallet 5 in a Dwight Lloyd type sintering machine and the sintering raw material layer 7 is formed. In the upper layer part 7a of the sintering raw material layer 7 supplied with a supplying device applying the magnetizing device 6 as the magnet drum, a carbonaceous supplying device 10 for laminating the carbonaceous material layer 12a is attached. As the carbonaceous material, powdery coke having about 0.5 mm grain diameter is used. The shortage of fuel source to the magnetized sintering raw material segregated in the upper layer part 7a is eliminated by adding the carbonaceous material in the upper layer, and the sintering is sufficiently promoted and the defective strength of the sintering can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for supplying a sintering raw material to a Dwyroid type sintering machine for producing sinter, which is one of the blast furnace charging raw materials. In the sintering material layer deposited on the pallet, mill scale,
Sintering materials such as magnetized sintering materials such as returned ore containing calcium ferrite are segregated in the upper layer of the sintering material layer, and the magnetized sintering material segregated in the upper layer is sufficient. The present invention relates to a method and an apparatus for supplying a sintering raw material that can be sintered to improve the yield of a product sintered ore.

[0002]

2. Description of the Related Art In order to produce sintered ore with a Dwyroid type sintering machine, first, limestone, serpentine, and ore mining are used as auxiliary materials for iron sources containing metallic iron such as powdered iron ore, iron sand, and mill scale. Then, the sintering raw material obtained by adding and mixing coke breeze, anthracite, and the like as a fuel source (charcoal material) is adjusted to about 7% moisture and granulated. Then, as shown in FIG. 6, a sintering raw material 2 in a feed hopper 1 provided in a Dwyroid L-type sintering machine is cut out using a drum feeder 3 and supplied to a plate-type sloping chute 4. The sintering raw material 2 segregates in particle size due to percolation (filtration and permeation) when sliding down on the sloping chute 4, and the fine sintering raw material in the lower layer and the coarse sintering raw material in the upper and middle layers. It becomes a segregated state.

[0003] Table 1 shows typical compositions of the sintering raw materials.

[0004]

[Table 1]

When the sintering raw material 2 thus segregated up and down is supplied onto the pallet 5 which continuously moves in the direction of the arrow from the lower end of the sloping chute 4, the upper and lower particle segregation is reversed. Then, the sintering raw material layer 7 having a predetermined thickness is formed with the relatively fine sintering raw material segregated in the upper layer and the coarse sintering raw material segregated in the middle and lower layers. Thereafter, the surface layer of the sintering raw material layer 7 is ignited by an ignition burner (not shown),
The pallet 5 is advanced toward the rear end of the sintering machine while the air above the sintering material layer 7 is sucked downward from a great bar (not shown) provided on the pallet 5 by an air blower (not shown). In the process of sintering, the sintering raw material 2 is sintered, thereby producing a sintered ore.

At this time, the particle size distribution and composition distribution of the raw material deposited in the height direction of the sintering raw material layer have an important effect on the results of the sintering operation. That is, in the initial stage of ignition by the ignition furnace,
By suction from below the pallet 5, air passes through the inside of the sintering raw material layer 7 whose surface has been ignited downward from the surface. At this time, the normal-temperature air is supplied without being preheated to the sintering melting zone (for example, a region of 1200 ° C. or higher) formed in the upper layer of the sintering raw material layer 7. On the other hand, during and after the sintering, the air sucked downward passes through the sintering completion region formed in the upper layer portion of the sintering raw material layer and is preheated. It is supplied to the sintering molten zone formed in the lower layer.

[0007] Therefore, the upper layer of the sintering raw material layer has a lower temperature in the layer than the middle and lower layers, and the time during which it is maintained at a high temperature is short, so that the sintered ore produced in the upper layer has a low degree of fusion bonding. Therefore, there is a problem that the strength of the sintered ore is low, and the yield of the sintered ore is reduced. Therefore, in recent years, as a method of supplying the sintering raw material, segregation charging that intentionally changes the raw material particle size distribution and the carbon content in the height direction of the sintering raw material layer deposited on the pallet has been actively adopted, This has helped to solve the above problems.

For example, in Japanese Patent Application Laid-Open No. 61-223136,
By providing a screen made of a plurality of strips extending along the flow of the sintering raw material supplied on the pallet, the density of the sintering raw material layer formed after the supply on the pallet is reduced, and the upper layer portion is formed. It is stated that by setting the fine grains in a segregated state in which coarse grains are deposited in the middle and lower layers, it is possible to achieve an improvement in sinter ore yield and an improvement in productivity by improving air permeability in the upper layer. However, this method has a problem that a sintering material having a water content of about 7% adheres to a plurality of strips, and it is difficult to stably maintain the initially expected segregation state of the sintering material layer. Was.

Further, Japanese Patent Application Laid-Open No. 58-133333 discloses a method of arranging an electromagnet in a sintering raw material supply device and supplying a sintering raw material to a pallet while applying a magnetic force to the sintering raw material falling by the electromagnet. Is disclosed. Specifically, an electromagnet is attached to a roll feeder or the like provided below the feed hopper, and the electromagnet exerts a magnetic force on metallic iron (Fe) present in the sintering raw material being supplied, and the falling speed And soft supply of raw materials. At the same time, the raw material particles having a small particle size are relatively more affected by the magnetic force than the material particles having a large particle size, so that the smaller the particle size, the lower the falling speed, and the larger the particle size, the earlier the particles fall and deposit on the pallet. It is stated that coarse particles are supplied to the lower layer of the sintering raw material layer and fine particles are supplied to the upper layer, so that a segregated state is obtained in the sintering raw material layer.

However, when the electromagnet is attached to the drum feeder, the segregation is inverted when the raw material segregated here is thrown from the drum feeder onto the sloping chute, which may have an adverse effect. It is also conceivable to separate the attached Fe component by repeatedly turning the electromagnet on and off, but this has the problem that the magnetic field action and the separation action are not continuous, stable segregation cannot be obtained, and the efficiency is poor. Dots remain.

In order to solve such a problem, Japanese Patent Application Laid-Open No. 9-302422 discloses that a magnetic force is applied to a flow of a sintering raw material falling from a ramping chute onto a pallet, and the magnetized sintering raw material is magnetized. The magnetizing sintering material is attracted to the lower layer side of the sintering material and magnetized. It is disclosed to provide a magnetizing device such as a magnet drum for segregation.

As shown in FIG. 4, a magnetic force is applied to the sintering raw material 2 sliding down the slopping chute 4 by a magnet drum 6 to cause segregation of the magnetized sintering raw material. Is formed into two layers, an upper layer portion 7a and a lower layer portion 7b where the magnetized sintering raw material is segregated. Here, reference numeral 8 denotes a main scraper, which has a function of scraping the magnetized sintering material adhered to the magnet drum 6 onto a pallet.

FIG. 4 shows an example in which a magnet drum is used as a magnetizing device. For example, a magnetizing device may be provided by providing a magnet on the back side of a ramping chute.
Japanese Patent Application No. 9-302422 discloses several specific examples of giving a magnetic force to a magnetized sintering raw material. By segregating a large amount of ferromagnetic and sinterable magnetized sintering raw material in the upper layer of the sintering raw material layer in this manner, the sintering raw material which has conventionally had a problem in strength is It is said that the strength of the upper layer of the layer was improved, and the strength of the entire sintering raw material layer was improved.

[0014]

However, although the magnetized sintering raw material can be segregated in the upper layer of the sintering raw material layer, the carbon material such as coke breeze and the like is indispensable for sufficient sintering. In other words, the carbon material remains homogeneously mixed in the sintering material layer, and only slightly fine coke segregates in the upper layer, and the upper layer is slightly higher in the distribution ratio of the carbon material. That's all. Therefore, there is a problem that the sintering of the magnetized sintering raw material is not always performed sufficiently, and it is not possible to obtain sufficient sinter strength and sinter yield.

The present invention solves the above-mentioned problems, obtains sufficient sinterability as a whole, including the upper part of the sintering raw material layer, and yields the product sintered ore (hereinafter referred to as sintering yield). The purpose is to improve.

[0016]

According to the present invention, there is provided a sintering method in which a sintering raw material is cut out from a feed hopper using a drum feeder and supplied to a pallet of a Dwyroid type sintering machine to form a sintering raw material layer. In the method of supplying raw materials, when a sintering raw material cut out using a drum feeder is supplied onto a pallet, a magnetic force is applied to the flow of the sintering raw material by a magnetizing device installed between the drum feeder and the pallet, and The magnetic sintering raw material is attracted to the lower layer side in the flow of the sintering raw material, and after segregating a large amount of the magnetic sintering raw material on the upper layer of the sintering raw material layer formed on the pallet, The above problem was solved by a method of supplying a sintering raw material, which comprises supplying and stacking a carbon material, which is one of the sintering raw materials.

Also, there is provided a sintering raw material supply device for forming a sintering raw material layer on a pallet of a Dwyroid type sintering machine, comprising a supply hopper for supplying the sintering material, and a supply hopper supplied from the supply hopper. A drum feeder for cutting out the sintering raw material, and a magnetizing device installed between the drum feeder and the pallet to apply a magnetic force to the flow of the cut out sintering raw material to attract the magnetized sintering raw material to the lower layer side in the flow of the sintering raw material. When,
A carbon material supply device for supplying and laminating a carbon material, which is one of the sintering materials, to a further upper portion of the upper layer portion of the sintering material layer formed on the pallet; The above problem has been solved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of a sintering raw material supply apparatus according to the present invention. In the present invention, the carbon material layer 12a is further provided on the upper layer portion 7a of the sintering material layer 7 supplied by the sintering material supply device to which the magnetizing device 6 as the magnet drum is applied.
A carbon material supply device 10 for laminating carbon is provided.

The carbonaceous material supply device 10 cuts out the carbonaceous material stored in the coal supply hopper 11 using a drum feeder 13 and supplies it to the pallet 5 via a plate-type sloping chute 14. Raw material layer 7
And a carbonaceous material layer 12a is further laminated thereon.
As the carbonaceous material, it is preferable to use fine coke powder having a particle size of about 0.5 mm. For example, fine powder of anthracite may be used in combination.

By adding the carbon material to the upper layer in this way, there is no shortage of a fuel source for the magnetized sintering material segregated in the upper layer portion 7a of the sintering material layer 7, and sintering is sufficiently promoted. This makes it possible to prevent sintering strength defects and the like. Here, as shown in Table 1, the coke used as a carbon material is about 4.1%, but the coke (supplied as a blended raw material from the mining hopper 1) previously added to the blended raw material is 3.5 wt%. 0.6 wt% of coke breeze (supplied from coal hopper 11) supplied solely from the material supply device 10
Is a preferable distribution ratio.

By allocating in this manner, the sintering raw material layer 7
It is possible to supply coke as a fuel source sufficient to sinter the upper layer portion 7a. Furthermore, according to the present invention, both the sintering raw material having excellent magnetizability and sinterability and the carbonaceous material such as coke breeze are supplied to the surface layer of the sintering raw material layer by milling, returning ore, etc. The synergistic effect has made it possible to greatly improve the sintering yield.

Here, in the sintering raw material supply apparatus of the present invention, as shown in FIG. 2, a large magnet drum 21 having a sub-scraper 18 is used instead of the sloping chute 4 and the magnet drum 6 in FIG. You may do it. In FIG. 2, a large magnet drum 21 performs the functions of the sloping chute 4 and the magnet drum 6 of FIG. The large-sized magnet drum 21 is a cylindrical magnet drum, for example, is composed of an inner ring and an outer ring provided concentrically, and the inner ring is a fixed type that does not rotate and the material is not specified, but the sintering material contacts the outer peripheral surface thereof A plurality of permanent magnets are arranged and mounted on the side to be brought close to the inner peripheral surface of the outer ring.

The sub-scraper 18 is a magnet drum 21
The magnetized material is a projection provided on the outer peripheral surface of the magnet drum 21. When the projection is out of the permanent magnet arrangement area, the raw material that has been magnetized easily falls and performs a scraper function.
This is effective in reducing the wear of steel. Further, as shown in FIG. 3, it is also possible to replace the sloping chute with a belt conveyor type sloping chute 20. The belt-conveyor-type sloping chute 20 has a structure in which an endless belt 19 is driven by being wound around a driving-side magnet drum 6 and a driven-side drum 17, and the sintering raw material 2 cut out from the drum feeder 3 is palletized. This makes it possible to make the flow falling upward smoother. Here, the driving direction of the endless belt 19 is free to rotate forward and reverse to adjust the falling flow of the sintering raw material 2. That is, if the rotation direction of the magnet drum 6 is set to the same direction as the sliding direction of the sintering material 2, the falling speed of the sintering material 2 can be increased,
If the direction is reversed, the falling speed can be reduced. Therefore, the state of the raw material segregation can be observed and the rotation direction and the rotation speed can be adjusted to be optimal.

[0024]

EXAMPLE As a result of applying the sintering raw material supply apparatus of the present invention to a sintering machine, a sintering yield was significantly improved. Table 2 shows the results of the sintering yields of the present invention to which the present invention is applied and the results of sintering yields thereof based on the results of operating some conventional examples.

The effective grate area of the sintering machine is 410 m ²
The sintering raw materials used were the compounding raw materials shown in Table 1.
The sintering material layer thickness is 450 mm.

[0026]

[Table 2]

In Table 2, the examples of the present invention are results when the apparatus for supplying a sintering raw material of the present invention shown in FIG. 1 is applied. Further, Conventional Example 1 is a result in the case of applying the sintering raw material supply device provided with the magnetizing device shown in FIG. Conventional example 2 is a result in the case where the supply device of the sintering raw material which combined the mineral supply hopper without a magnet drum and the carbonaceous material supply device as shown in FIG. 5 is applied. Further, Conventional Example 3 is a result in the case where the supply device of the sintering raw material only for the feed hopper without the magnet drum as shown in FIG. 6 is applied.

As is clear from Table 2, the yields of Conventional Example 1 and Conventional Example 2 both exceed the yield of Conventional Example 3.
In the present invention, it is shown that both of Conventional Example 1 and Conventional Example 2 are much larger. From the results in Table 2, it was found that according to the present invention, the sintering yield was significantly improved, and it was proved that the present invention was extremely effective.

[0029]

According to the present invention, the sintering yield can be greatly improved. Further, the conventional disadvantage that the sintering strength is weakened in the upper part of the sintering layer can be solved, and a uniform high-strength sintered ore can be produced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a sintering raw material supply device of the present invention.

FIG. 2 is a longitudinal sectional view of a sintering raw material supply device according to another embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a sintering raw material supply device according to still another embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a conventional sintering raw material supply device provided with a magnet drum.

FIG. 5 is a longitudinal sectional view of a sintering raw material supply device provided with a carbon material supply device.

FIG. 6 is a longitudinal sectional view of a conventional sintering raw material supply device.

[Explanation of symbols]

 Reference Signs List 1 Mining hopper 2 Sintering raw material 3 Drum feeder 4 Sloping chute 5 Pallet 6 Magnetizer (magnet drum) 7 Sintering raw material layer 7a Upper part (of sintering raw material layer) 7b Lower part (of sintering raw material layer) 8 Main Scraper 10 Carbon material supply device 11 Coal supply hopper 12 Carbon material (coke breeze) 12a Carbon material layer 13 Drum feeder 14 Sloping chute 17 Follower drum 18 Sub-scraper 19 Endless belt 20 Belt conveyor type sloping chute 21 Magnetizer (magnet drum)

Claims (2)

[Claims] In a method for supplying a sintering raw material for cutting a sintering raw material from a feed hopper using a drum feeder and supplying the cut sintering raw material onto a pallet of a Dwyroid type sintering machine, a drum feeder is provided. When the sintering raw material cut out by using the sintering material is supplied onto a pallet, a magnetic force is applied to the flow of the sintering raw material by a magnetizing device installed between the drum feeder and the pallet, and the magnetized sintering raw material is converted into the sintering raw material. After attracting the magnetized sintering raw material to the upper part of the sintering raw material layer formed on the pallet,
Further, a method for supplying a sintering raw material, comprising supplying a carbon material, which is one of the sintering raw materials, to the upper portion of the upper layer portion and laminating the carbon material. 2. A sintering raw material supply device for forming a sintering raw material layer on a pallet of a Dwyroid type sintering machine, comprising: a feed hopper for feeding the sintering raw material; and a feed hopper supplied from the feed hopper. A drum feeder for cutting out the sintering raw material, and a magnetizing device installed between the drum feeder and the pallet to apply a magnetic force to the flow of the cut out sintering raw material to attract the magnetized sintering raw material to a lower layer side in the flow of the sintering raw material. And a carbon material supply device for supplying and stacking a carbon material, which is one of the sintering materials, further above the upper layer portion of the sintering material layer formed on the pallet. apparatus.